1. Field of the Invention
The present invention relates to a weather strip, a method of manufacturing the same, and a molding device used in the same method.
2. Related Art
The manufacturing of a related art weather strip of this kind has been done by a known extrusion molding method in which an extruded member is formed in an elongated state. A molded member is then formed in a continuously connected state with respect to an end surface of the extruded member with a front section of the extruded member set in a molding device used to form the molded member.
The molding device used to continuously form the molded member includes a fixed mold, a plurality of movable molds and core molds. The core molds include core bodies for forming hollow portion, and core-extended plates extending from the core bodies. In order to form a molded member, an extruded member formed in advance by a known extrusion molding method is set first with each mold opened, in such a manner that an end portion of the extruded member is fitted in an end portion of the core body, the extruded member being thus fixed in the molding device. Next, each mold is disposed in a predetermined position, and the molding device is closed. At this point in time, molded member forming cavities are formed by the molds. Unvulcanized rubber is then injected into the cavities via a gate (not shown) and the like so as to fill the cavities therewith. The unvulcanized rubber is thereafter vulcanized. Each mold is opened, and core molds and vulcanized rubber (precursor of a molded member) combined together are removed. At this time, slits are formed in the precursor of the molded member owing to the existence of the core-extended plates.
When the core bodies are taken out from the slits, a hollow-carrying precursor of the molded member is obtained. The opposed openings of the slits are then joined together at a plurality of positions with an adhesive to obtain a molded member. In short, a weather strip in which this molded member and extruded member are combined together is obtained (refer to, for example, Japanese unexamined Patent Publication No. JP-S58-205749A).
In order to try to form the hollow portion in the whole longitudinal region of the molded member, the core body is necessarily provided over the whole longitudinal region of the molded member. When the easiness of the withdrawal of the core body is taken into consideration, it is desirable that the slits be also formed in substantially the whole longitudinal region of the molded member.
However, the slit becomes long in this case, so that it becomes necessary in many positions to bond the slit defining portions together after the core bodies are taken out. This causes the possibility that the operation man-hour and manufacturing cost necessarily increase to arise.
Since the slits are closed with an adhesive, the molded member is necessarily deformed in its width reducing direction. Therefore, it is necessary to design a product and molds with a deformation margin of the molded member estimated, and there is the possibility that this increases complexity and man-hour of the designing operation.